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  <title>Document</title>

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  <script>
    // absolute
    // console.log( Math.abs(-10) )
    // console.log( Math.abs(10) )
    // console.log( Math.abs(10) )

    // console.log( Math.floor(1.9) )   // 1
    // console.log( Math.floor(1.1) )   // 1

    // ceil
    // console.log( Math.ceil(1.9) )   // 2
    // console.log( Math.ceil(1.1) )   // 2

    // console.log( Math.round(  1.5 ) )  // 2
    // console.log( Math.round(  -1.5 ) )  //-1
  </script>
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